EDGARS OŠLEJA made his debut on the stage of the Latvian National Opera in 2015. Among the roles he has interpreted for the LNO are Sarastro in the Little Magic Flute, Reinmar von Zweter in Tannhäuser, Colin in La bohème, the Blind Man in I Played, I Danced, the Keeper of the Madhouse in The Rake’s Progress, and the White Priest in Turandot. In February 2020, Edgars Ošleja made his debut, as Colin in La bohème, on the stage of the Prague National Opera where he proceeded to sing Angelotti in Tosca, Banquo in Macbeth, the High Priest in Nabucco and Pharaoh in Aida. Ošleja has performed in concerts of academic music at the Sigulda Opera Music Festival, Riga Latvian Society House, Riga Anglican Church, and elsewhere. Accompanied by the Prague Opera Orchestra, he has sung the bass solo in Beethoven's 9th Symphony. In 2021, he took part in the premiere of Imants Kalniņš’s opera Matīss, kausu bajārs.  Ošleja’s repertoire includes arias and songs by Kaldár, Tchaikovsky, Handel, Verdi, Mozart, Prokofiev, and other composers.

In 2019, Ošleja graduated from Jāzeps Vītols Latvian Academy of Music, where he studied academic singing with Roberts Hansons, guest associate professor from the Latvian Academy of Culture. He has regularly participated in vocal masterclasses with Algirdas Janutas, Annika Olinkari, Roberts Haimans, and others. Ošleja has also attended masterclasses on the Alexander Technique conducted by prof. Patrick Krisatis, as well as classes in stage movement given by Marlene Smith, a teacher at the Royal Danish Opera Academy.

Edgars Ošleja received the Great Music Award 2021 as the Young Artist of the Year. In 2021, Edgars Ošleja won 1st prize in the Inese Galante’s Talent Competition. In 2017, he reached the semi-finals of the Antonina Kampi International Vocal Competition and was among the finalists in the Alīda Vāne International Vocal Competition.